The importance and value of using a variety of sources of knowledge in social work, including user experiences and knowledge, was explored in 2003 by the Social Care Institute for Excellence as a basis for its work over several years. Well worth a read if you can find it!
Pawson, R., A. Boaz, L. Grayson, A. Long and C. Barnes (2003). Types and quality of knowledge in social care. London, Social Care Institute for Excellence.
Pawson, R., Boaz, A., Grayson, L., Long, A. and Barnes, C., 2003. Types and quality of social care knowledge. Stage two: Towards the quality assessment of social care knowledge. ESRC UK Center for Evidence Based Policy and Practice: Working Paper, 18, pp.1-31.